Biology and management of rose leafhopper (Homoptera: Cicadellidae) on apple in West Virginia

Rose leafhopper, Edwardsiana rosae (L.), has 3 generations per year in eastern West Virginia. It overwinters and completes the 1st generation on rosaceous species such as multiflora rose. Adults of this generation migrate to apple where a 2nd and 3rd generation are produced. Seasonal monitoring at 2 locations for 2 yr revealed that adult populations peaked in mid-June (migration from other Rosaceae), early August, and early October. Nymphal populations peaked in early July and late August. Populations were lower at both locations in 1993 than in 1992. Esfenvalerate, endosulfan, and formetanate hydrochloride provided the most effective control through 2 wk after treatment, resulting in the lowest accumulation of leafhopper days. Of the botanical insecticides evaluated, ryania was significantly more effective than sabadilla and pyrellin, and provided control comparable with the best synthetic insecticides